Apparatus for manufacturing articles made of aluminum, aluminum alloys, light alloys and the like, and method performed by the apparatus

Abstract

An apparatus and method for manufacturing articles made of aluminum, aluminum alloys, light alloys and the like, the apparatus comprising a lower die section ( 12 ) and at least one upper die section ( 13 ), associated with corresponding press platens ( 14,15 ) for closure determining shape of the cast article, a vertically elongated duct ( 16 ) for introducing liquid metal, a pressurized furnace that leads into the lower die section ( 13 ) that forms at least one lower impression ( 17 ) with at least one concave portion for introducing liquid metal through at least one corresponding inlet ( 18 ) formed at the upper portion of the duct ( 16 ), a male plug ( 19 ) associated with the upper die section ( 12 ), and movable with respect thereto.

1 - 10 . (canceled)  
   
   
       11 . An apparatus for manufacturing articles made of aluminum, aluminum alloys, light alloys and the like, comprising a lower die section and at least one upper die section, which are associated with corresponding press platens for their closure so as to determine the shape of the article to be cast, a vertically elongated duct for introducing liquid metal that arrives from an underlying pressurized furnace leading into said lower die section, characterized in that said lower die section forms at least one lower impression that has at least one concave portion for introducing liquid metal through at least one corresponding inlet formed at the upper portion of said duct that rises from said lower die section, a male plug being associated with said upper die section, said male plug being movable with respect to said upper die section and forming an upper impression portion, said at least one upper die section being closable onto said lower die section, determining the shape of the article to be cast, and said male plug acting as a flow control element for said at least one inlet, whose overflow level determines the chosen quantity of liquid metal that is present inside said shape.  
   
   
       12 . The apparatus of  claim 11 , wherein said duct forms at its upper end, which rises from said lower die section, a plurality of contoured inlets for introducing liquid metal into one or more impressions whose lower portions define the corresponding overflow level.  
   
   
       13 . The apparatus of  claim 11 , wherein said male plug is arranged substantially coaxially to said duct and is provided in a lower region with an axial hollow whose cylindrical wall is suitable to close said inlets, by arrangement thereof at their overflow level, to cause a clean separation between the liquid metal that is present within said duct and the metal that is present within said shape.  
   
   
       14 . The apparatus of  claim 11 , wherein said male plug cooperates to form the shape of the article being cast when it is arranged at a height that is lower than the overflow level of said inlets.  
   
   
       15 . A method for manufacturing articles made of aluminum, aluminum alloys, light alloys and the like, comprising the steps of: 
 closing said die sections while the male plug is arranged at a higher level than the overflow level of said inlets,    introducing liquid metal into the shape formed by said die sections, through said inlets, until it is filled completely,    lowering said male plug to the overflow level of said inlets until they are closed, causing a clean separation between the liquid metal that is present within said duct and the metal that is present within said shape,    waiting for the casting to solidify,    opening said die sections and removing the cast article.    
   
   
       16 . The method of  claim 15 , further comprising, after the step of lowering said male plug to the overflow level of said inlets, a step of further lowering of said male plug until the intended shape of the article being cast is obtained.  
   
   
       17 . The method of  claim 15 , wherein said step of introducing liquid metal in the impression while the overflow level of said inlets is arranged at a higher level than the highest point of said shape, consists in 
 making liquid metal rise from said pressurized furnace through said duct to a higher level than said overflow level until said shape is completely filled,    lowering the level of liquid metal of said duct.    
   
   
       18 . The method of  claim 15 , wherein said step of introducing liquid metal into the impression while the overflow level of said inlets is arranged at a lower level than the highest point of said shape, consists in 
 making liquid metal rise from said pressurized furnace through said duct to a higher level than said overflow level until said shape is completely filled,    keeping said liquid metal pressurized.    
   
   
       19 . The method of  claim 16 , further comprising, after the step of further lowering said male plug until the intended shape of the article being cast is obtained, a step of: 
 removing pressure from said pressurized furnace,    lowering the level of liquid metal of said duct.    
   
   
       20 . The method of  claim 17 , further comprising, before said step of introducing liquid metal in the impression, a pre-dosage step of: 
 making an amount of liquid metal, dosed according to preset requirements, rise from said pressurized furnace through said duct.